Tuesday, April 18, 2017

Thayne Elementary Weather Station and an Aid to Spring Planting

Thayne Elementary Weather Station and an Aid to Spring Planting.

Thayne Elementary Weather Station

A Davis Weather Station was installed  at Thayne Elementary School in September 2010 and has been transmitting data since 3pm  September 22, 2010.   On August 15, 2011 the sensors for both soil temperature and moisture were added to the station.

Following is a graph for the most recent year of daily maximum and minimum temperatures from the weather station.
Max and Min Temperatures from May 1 2016 to April 17 2017

It is interesting to look at the data which has been collected with the soil moisture and temperature sensors.

The first temperature sensor is located just below the surface on the school  grounds with the  2nd sensor buried at a depth of one foot and the third at 2 feet.

When looking at the sensor located just below the surface, it is surprising to see the large range of temperatures on particularly sunny days.  Following is an example of data for the soil temperatures

Near surface Thayne Elementary  temperature

However the 1 foot and 2 foot sensors tell a much different story with both dropping to freezing early in January and remaining there until the last week in March.

Thayne Soil Temperature at a depth of one foot

Thayne Soil Temperature at a depth of two feet.
The sensors currently are available from Spring until Fall.  Below is the graph of the 3 levels of temperatures for most of April 2016. The orange is just below the surface while Blue is one foot and green two feet below the surface.

Three levels of soil temperatures from April 13-30 2016

Moisture at one(green) and two(red)  foot levels
The moisture sensor indicates fairly high soil moisture content.

The current reading of 9-12 centibars is a very moist soil.  It will be interesting to see how this sensor responds during summer  It can be observed any time on line at

For additional information (as to what this measurement suggests) the following  is helpful:

General rule of thumb for interpretation: 

Soil moisture is nearing a critically dry level when soil tension (indicated by the centibar meter reading) reaches a level that corresponds to more than 50 percent depletion of the plant available water at a specific soil depth.  The critical soil  tension level that corresponds with 50 percent depletion levels will vary depending upon soil type because of different soil porosity characteristics..   For example, a soil  tension reading of 35 centibars may indicate that a very sandy soil will approach 50 percent depletion of plant available soil moisture but for a loam/silt loam soil 50 percent depletion may  not be approached until tension readings approach 110 to 130 centibars.

Following is a guideline as to when to plant vegetables for optimal germination.  Using the temperature data from the Thayne Weather Station should aid that decision.

No comments:

Post a Comment